The present invention relates to improvements in cassette tape cartridge systems.
In the conventional tape cassettes, as shown in FIG. 2, thin sheets 2, 2 made of a film of tetrafluoroethylene and so on are mounted inside cassette halves 1 so that the cassette half 1 does not directly contact a reel hub 4 and/or a wound tape body. However, when the sheet 2 is used in a rectangular form having almost the same size of the conventional cassette half, the tape is undesirably stretched or braked by the sides with the increase of the time for using the cassette tape. As a result, bad influences upon the reproduction of sounds have been caused. Both sides of the tape become deformed, and accordingly, the frictional force contacting to the sheet increases with the rotation of the tape, resulting in increasing the take-up torque which renders the tape unrotatable or causes unevenness of rotation. Moreover, due to the long period of use, not only the tape, but the surface of the sheet becomes coarse, which results in increasing the frictional force.